The purpose of these secondary analyses was to examine relationships between patient factors and patient-provider decision-making style (PDM) on heart-healthy behavior changes in 142 adults with diabetes after hospitalization for an acute coronary syndrome (ACS). A clinical trial randomized adults to either control or a telephone coaching intervention. Generalized estimating equations were used to analyze the relationship between patient factors and PDM style on longitudinal postdischarge changes in three heart-healthy behaviors, avoiding high fat foods, weight loss, and increased physical activity. Neither PDM style nor telephone coaching intervention affected heart-healthy behaviors in this population. Although adults with diabetes preferred collaborative patient-provider decision-making, present levels of provider engagement were not sufficient to support behavior change. Results suggest the need for sustained and tailored nursing interventions to facilitate heart-healthy behavior changes in adults with diabetes after ACS hospitalization.